Supporters then turned on each other in the stands, fighting among themselves.

Ultras have declared war on the Croatian FA (HNS) who they accuse of being corrupt, and have previously protested against the regime of president Davor Suker and vice president Zdravko Mamic by burning a swastika into the pitch before a qualifier against Italy.

The Croatian FA are under investigation following crowd trouble in last week's clash with the Czech Republic (Image: REUTERS/Max Rossi)

Flares were thrown onto the pitch during the unrest (Image: Getty)

Ultras accuse the Croatian FA of being corrupt and want their team to be thrown out of the Euros (Image: Getty)

Now they have vowed to disrupt Croatia’s upcoming clash with Spain in Bordeaux and posted a map on Facebook, including crudely-drawn arrows indicating their plan of attack.

The Ultras also claim to have reinforcements in the shape of another group - the U.V. - in addition to a pre-existing alliance of thugs from various Croatian clubs.

The plan for Tuesday's game with Spain (Image: Facebook)

The plan for St Etienne last week (Image: Facebook)

“Maybe it would be best if we don’t play at all,” said Ivan Perisic, who scored the opening goal for Croatia in the 2-2 draw with the Czechs. “Maybe that would actually be better in case these things are going to happen every time we play.”

The coach, Ante Cacic, added: “We are all to blame. Let’s not start washing our hands from it.”